The present invention relates to an anti-extrusion device for supporting an inwardly compressed seal which is sealing around the outside diameter of a conduit such as a pipe.
Various types of seals have been disclosed for sealing on the outside diameter of a pipeline, such as in my U.S. Pat. No. 5,056,830. The seal and actuating mechanism must be sufficiently retracted to an unactuated position in order to allow the sealing mechanism to receive or be inserted over the outside of the pipe. However, when the seal is compressed and moves inwardly to engage and set and seal against the outside of the pipe the backup supports on each end of the seal do not engage the outside of the pipe thereby leaving a gap or space into which the seal is extruded upon setting. Such extruded seals are subject to failure because they are not able to accomplish their intended function of sealing off against the required pressures.
The present invention is directed to an anti-extrusion device for engaging the outside of a conduit and the opposite ends of a seal and limiting its extrusion thereby allowing the seal to properly set and hold higher pressures.